At the marriage of Cadmus and Harmonia, Iasion was lured by Demeter away from the other revelers. They had intercourse as Demeter lay on her back in a freshly plowed furrow. When they rejoined the celebration, Zeus guessed what had happened because of the mud on Demeter's backside, and out of envy killed Iasion with a thunderbolt.[3][4] Some versions of this myth conclude with Iasion and the agricultural hero Triptolemus then becoming the Gemini constellation.